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Thermally sprayed WC-based hardmetal coatings offer high hardness, good sliding wear and abrasion performance and find large applications in mechanical engineering, valve construction, or offshore applications. WC-Co coatings are mainly produced by high-velocity oxy-fuel spraying (HVOF) from conventional spray feedstock powders. In this work, suspension-HVOF spraying (S-HVOF) was used to produce dense-structured WC-12Co coatings and their microstructural, mechanical and tribological properties were investigated. Significant work was devoted to the development of appropriate aqueous suspensions starting from commercially available fine WC and Co raw powders feedstock. Suspension spraying was carried out using gas-fuelled HVOF TopGun system; for comparison purposes, liquid-fuelled HVOF K2 was employed to spray WC-12Co coatings starting from commercially available spray powder. Microstructural characterization, x-ray diffraction and microhardness of the coatings were evaluated. Oscillating sliding wear tests were conducted against sintered alumina and WC-6Co balls. The sliding wear performances of the WC-Co sprayed coatings were discussed in term of their microstructure, phase composition and coating-ball test couples.

By adjusting the thermal spraying suspension technology, coatings with excellent microstructure, surface morphology, and phase composition can be obtained to meet the application needs in mechanical, electrical or friction fields. The use of suspensions as feedstock material allows a high degree of flexibility with regard to the chemical composition of the sprayed coatings. Moreover, suspension thermal spraying (STS) is a promising technique for the production of coatings, the use of which was previously limited by expensive starting materials. A mixture of less expensive starting materials in the suspension and an "in situ" reaction to the desired product during the spraying process make this possible. Zn2TiO4 coatings are one example where the high costs of blended oxide powders as feedstock material hinder the market introduction, whereas their outstanding electrical properties and photocatalytic activity are of great interest for various industrial applications. In this work, single oxides ZnO and TiO2, Zn acetate salt as ZnO precursor, as well as a Zn2TiO4 powder were used to develop tailored aqueous suspension feedstocks suitable for thermal spraying. To follow the formation of the compositions in the system ZnO-TiO2, differential thermal analysis (DTA) measurements were performed. Preparation routes of stable suspensions and suspension-solution mixtures with low sedimentation rates, low viscosities and good flowabilities are discussed. Microstructures and phase compositions of sprayed coatings are shown, and the “in situ” formation of Zn2TiO4 phase during Suspension High Velocity Oxygen Fuel Spraying (S-HVOF) is demonstrated. This work shows the high potential of suspension feedstocks from single oxide raw materials to obtain Zn2TiO4 sprayed coatings.

Autonomous Vehicles (AVs) will soon be a reality on our roads. Up to now, their standard behaviour is predetermined since it is the result of programmed algorithms. Under risky traffic situations, however, they will face dilemmas such as, deciding between affecting the passenger or affecting others. Thus, in this experiment, we investigate how people solve a reframed version of the well-known Trolley-problem [Foot, P. 1967. “The problem of abortion and the doctrine of double effect,” Oxford Review 5: 5–15] under two conditions: when subjects actually drive a vehicle simulator, versus when they solve the same dilemma by programming a hypothetical AV. In both settings, the participants’ decisions have real monetary consequences, which affect others and themselves. Our Probit models indicate that subjects who program an AV and who are more cautious in terms of speed are less (more) likely to sacrifice a pedestrian (themselves) compared to those who actually drive and prefer a higher driving speed. Moreover, we find that the subjects’ choices are associated with risk aversion but not with moral beliefs or loss aversion. Implications of the driving vs programming discrepancies for the design of AVs algorithms are discussed.

This work deals with facility location in a physical internet environment. Three questions are being dealt with. What is a suitable number and spread of via-point locations for a CCL-concept, how sensitive does the number of via point location react to changes in transport costs and how can the relevant cost parameters roughly be estimated? In a reduced complexity setup, i.e. a two level transportation chain, we compute a total of 8 different structural scenarios using different generative approaches and compared their cost structures.

Thermally sprayed WC-Co coatings provide excellent wear resistance and corrosion protection under heavy loads, but their application usually involves additional grinding and polishing steps, which can be 3-4 times costlier than the spraying process itself. There is thus the motivation to develop a process that produces smooth, near-net-shape carbide coatings. This contribution is an investigation of WC-12Co coatings obtained by suspension HVOF spraying. Significant work was devoted to the development and characterization of water-based hardmetal suspensions synthesized from commercially available WC and Co powders. The suspensions produced were sprayed using the HVOF process, and the resulting coatings were evaluated based on microstructure, hardness, and phase composition.

The future of urban transport (including passenger transportation and goods logistics) may develop in significantly different directions. Depending on changes in urban behavior, and depending on decisions made by lawmakers and governmental bodies, as well as by commercial players, this future may show a significantly reduced mobility of people and goods (for example, as depicted in the motion picture The Matrix, where people live immobilized in cocoons) or a significantly increased mobility (for example, as depicted in the motion picture The Fifth Element, where multiple layers of air traffic are added to road and rail traffic). We applied a systems thinking method to create a model for political decision makers and researchers. This model can contribute to a better understanding of the interrelations of societal factors (e.g., behavioral changes in the current COVID-19 situation), technological factors (e.g., the role of data traffic or emerging urban air traffic) and environmental factors (e.g., noise or CO2 emissions) in an urban mobility and logistics system. The research also shows that data traffic has the potential to partially substitute physical passenger and goods traffic under certain circumstances. Thus, data networks should conceptually be regarded as a new mode of transport that plays a role in the urban modal split.

Social peace is an asset to every society. Its absence endangers the well-being and the safety of the population and the stability of states. In order to better understand the interdependencies of poverty, social peace and migration pressure the authors introduce the model of the “Edgeworth-Cube” which is an extension of the classical Edgeworth Box model by one dimension. This new dimension can either be interpreted as “aggression” (which reduces “social peace” for others) or as “migration pressure” (which results from a worldwide heterogeneous distribution of wealth), and this new dimension is modelled as a non-budget-constrained unilateral immaterial good. The “Edgeworth-Cube” also differentiates vital (essential) goods from normal (non-essential) goods. By focusing on extremely imbalanced endowments and by formal mathematical modeling the authors show in their approach that applying behavioral pressure (i.e. aggression or migration pressure) has an existential economic value for the poor on the one hand. On the other hand, the authors show that transfer payments have a systemically limited potential to keep aggression and migration pressure at bay.

Compositions in the system Cr2O3-TiO2-Al2O3 are among the most used ceramic materials for thermally sprayed coating solutions. Cr2O3 coatings present good sliding wear resistance; Al2O3 coatings show excellent insulation behavior and TiO2 striking corrosion properties. In order to combine these properties, coatings containing more than one oxide are highly interesting. The conventional spraying process is limited to the availability of binary feedstock powders with defined compositions. The use of suspensions offers the opportunity for tailor-made chemical compositions: within the triangle of Cr2O3-TiO2-Al2O3, each mixture of oxides can be created. Criteria for the selection of raw materials as well as the relevant aspects for the development of binary suspensions in the Cr2O3-TiO2-Al2O3 system to be used as feedstock for thermal spraying are presented. This formulation of binary suspensions required the development of water-based single-oxide suspensions with suitable behavior; otherwise, the interaction between the particles while mixing could lead up to a formation of agglomerates, which affect both the stability of the spray process and the coating properties. For the validation of this formulation procedure, binary Cr2O3-TiO2 and Al2O3-TiO2 suspensions were developed and sprayed using the S-HVOF process. The binary coatings were characterized and discussed in terms of microstructure and microhardness.

This article describes how there exists ample experimental evidence demonstrating a positive wage-effort relationship in which the results from the employee's effort lead to deterministic firm payoffs. The authors thus investigate a reframed version of the gift-exchange game in which the firms' payoffs can take two values, one of them is randomly determined by an external process after the effort choice has been made. They find that effort levels are significantly lower when payoffs are probabilistic than when they are deterministic. As a consequence, high waging is profitable in the deterministic, but not in the probabilistic condition. Moreover, the treatment effect is strongest among firms which offer high wages.

Autonomous Vehicles (AVs) will soon be a reality on our roads. Up to now, their standard behaviour is predetermined since it is the result of programmed algorithms. Under risky traffic situations, however, they will face dilemmas such as, deciding between affecting the passenger or affecting others. Thus, in this experiment, we investigate how people solve a reframed version of the well-known Trolley-problem (Foot, 1967) under two conditions: when subjects actually drive a vehicle simulator, versus when they solve the same dilemma by programming a hypothetical AV. In both settings the participants’ decisions have real monetary consequences, which affect others and themselves. Our Probit models indicate that subjects who program an AV and who are more cautious in terms of speed are less (more) likely to sacrifice a pedestrian (themselves) compared to those who actually drive and prefer a higher driving speed. Moreover, we find that the subjects’ choices are associated with risk aversion but not with moral beliefs or loss aversion. Implications of the driving vs programming discrepancies for the design of AVs algorithms are discussed.

A methodology was developed to evaluate the operational suitability of electromobility concepts for last-mile delivery operations. Electromobility systems consisting of electric vehicles of ten weight classes and four mid-operation charging strategies were synthesized and evaluated using a hypothetical grocery outlet replenishment scenario. A system of operational suitability indicators was developed based on the amount of and efficiency of resources needed. The results highlight a strong trade-off between single-charge driving range, payload capacity, and the minimum fleet size needed. If operational performance similar to that of diesel vehicles is to be reached, mid-operation charging could be a reasonable alternative to “simply” having a bigger vehicle battery. NRF (Natl Research Foundation, S’pore) Published version

Concepts for city logistics require the cooperation between several types of stakeholders. As different stakeholder types have different objectives and different decision spaces, we suggest a top-level qualitative approach (system thinking) to model the interdependencies of the different factors which are influenced by these stakeholder decisions. We also suggest using this qualitative system thinking model as a meta-structure for further quantitative sub-models (as e.g. system dynamics models). We present a methodological approach to create such a meta-structure (i.e. a system thinking model) and give an example on how this meta-structure can be expanded by quantitative sub-models.

How will logistics in cities be carried out in the midterm future? To answer this question an overview of different existing and emerging transport logistics operations is provided, the pros and cons of these different operations are set out. Based on these findings a partial qualitative systemic model is presented which shows how these operations are influenced by global and logistics trends on the one hand and by delivery service requirements on the other hand. Based on this model a vision of urban logistics in Europe in the year 2030 as well as the concept of “Post 4.0” is presented.

In a principal-agent setting, offering maximum levels of incentives, i.e., the compensation is completely variable, is far from optimal because this reduces the principal`s profits, and because the risk-aversion nature from the agent matters. In this paper, we hypothesize that an incentivized agents’ risk-taking about the composition of their own wage structure can offset the typical risk-aversion, and thus lead to an increase in performance. Using a reframed version of the gift-exchange game workers decide, before their effort choice, how much of their wage is variable and fixed. The variable component is limited to max. 30% of the initial wage offer (the rest remains fixed) and it increases/decreases with effort and also with a random factor. We find that risk-averse workers exposed ¾ of their variable component to risk, and outperformed a control group (fixed wage scheme) by half in effort levels. This increase in effort is positively correlated to their risk-distributional preferences. Theoretical explanations (supported by data) are discussed.

PurposeThe aim of this paper is to offer insights into what consumers are looking for when downloading music and what different consumer groups might look for in commercial online music services, based on their current level of music downloading, and their likelihood of purchasing music online in the near future.Design/methodology/approachThe literature review focused on the risk and adoption theories. Interviews were used to help derive variables used in the design of a questionnaire. A web survey of 211 samples was used as a data collection method for this study.FindingsThe results suggest that performance and time‐loss aspects of perceived risks are playing an important role, while social and psychological aspects of risks are of the least concern to consumers. Where different types of users are concerned, those with the most experience of downloading music are the least profitable segment to target. Non and Light downloaders, on the other hand, should be the focus of marketing activities, although their needs are different.Originality/valueThis paper highlighted that different groups have different behaviours towards downloading music. The finding helps the online music providers to focus on and capture the new age downloaders.

Telematics solutions for logistics and fleet management (LFM telematics) are becoming an integral element of many transport operations. The key benefit of LFM telematics is to integrate the former “black box transport process” transparently into the processes of the shipper and the consignee. In addition to this, it allows the transport operator to plan, monitor, and adjust operations in accordance with the needs of its customers and in accordance with his or her own profitability needs. Finally, LFM telematics helps to simplify the driver's workload. In this chapter, the process context of LFM telematics is discussed and a three-tier model for LFM telematics is introduced. With reference to this three-tier model, the usage of LFM telematics in different vertical industries, for example, automotive, construction, courier, express, parcel, and mineral oil, is explained. Finally, technical components and data needed to build an LFM telematics solution are outlined. Keywords: digital tachograph; electronic on-board recorder; fleet monitoring; process standardization; telematics; track and trace

In der Regel wachsen die Transportkosten auf der letzten Meile mit der Enge des Lieferzeitfensters. Dies stellt insbesondere Anbieter vor ein Problem, die Aussagen uber einen prazisen Liefertermin bei Bestellung abgeben mussen, obwohl noch nicht alle zu bedienenden Lieferungen bekannt sind.